The app now provides one ranked list of video suggestions
instead of the previous, tiered selection that had
categories like "Watch again" or "Recommended by [insert friend's
name here]."

In the old format, you could see many more options with less
scrolling. In this new format, YouTube's betting that its
first few recommendations will be so good that you'll want to
click in. Its deep neural network systems factor in
your geographical data, watch history, device, how much
you've watched a given video or channel in the past, and
more.

In the company's beta tests with its new system,
people did indeed spend more time watching with the ranked
video list.

"The reason we were able to do this is that we’ve made so
many changes to our machine learning systems that we can now tell
what users most likely want to watch," YouTube says in a
statement.

The improvement touches on one of YouTube on-going challenges:
Getting users to think of it as a destination for discovery
instead of a just a repository for any kind of content they might
want to look up.

There are 400 hours of video uploaded to YouTube
every minute so if you're looking for something
specific, the site is likely going to have the right kind of
content to suit you. But it also wants people to open the app
and find things they didn't even know they wanted.

As Facebook — the ideal place for discovering clips you
weren't specifically looking for — amps up its own video
reach, YouTube needs to prove it can do both more than
ever.